Multiple member interconnect for surgical instrument and absorbable screw fastener

ABSTRACT

An absorbable screw fastener and a method of firing with an applicator capable of applying a surgical fastener to tissue in order to form tissue connection to secure objects to tissue, the fastener including a body portion having a helical thread, a head portion disposed at the proximal end of the body portion. The head portion includes a driver receiving configuration on its outer surface. The screw fastener further includes a cannulated center lumen with an opening extending from the head portion through the longitudinal length of the body portion.

RELATED APPLICATIONS

This application claims priority to International Patent ApplicationPCT/US2004/018702 filed Jun. 14, 2004 which claims priority to U.S.Provisional Patent Application Ser. No. 60/478,352 filed Jun. 13, 2003,the disclosures of which are incorporated herein in their entirety bythis reference.

BACKGROUND OF THE INVENTION

1. Technical Field

The present disclosure relates generally to surgical fasteners, surgicalfasteners appliers and methods for connecting body tissue and, moreparticularly, to bio-absorbable screw fasteners, screw fastenerappliers, and methods of using the screw fastener applier to firemultiple absorbable screw fasteners to a target surgical site.

2. Description of Related Art

Surgical fasteners are used to eliminate the need for suturing, which isoften time consuming and inconvenient. Surgical fasteners accomplish inseconds what would have taken many minutes to accomplish by suturing,thus reducing operating time and trauma to the patient. In hernia repairprocedures, for example, the weakened area of the abdominal wall may bereinforced with a synthetic mesh or by suturing the abdominal tissue. Insuch an instance, a surgical fastener in the form of an absorbable screwfastener may be used, in lieu of, or in addition to, a surgical sutureto fix the position of the mesh.

In view of the widespread use of surgical fasteners, a continuing needexists for improved surgical fasteners, surgical fastener appliers, andmethods of applying the surgical fasteners.

SUMMARY

Accordingly, the present disclosure relates to an absorbable screwfaster to form tissue connections, the absorbable screw fastener havinga head configuration which permits the use of a combined rotationalforce and linear force to facilitate insertion. The absorbable screwfastener is tacked into body tissue to form tissue connection to secureobjects such as a mesh material to tissue.

In one embodiment, the absorbable screw fastener includes a body portionhaving a helical thread, a head portion disposed at the proximal end ofthe body portion and a blunt end at a distal portion of the bodyportion. The head portion includes a driver receiving configuration onits outer diameter, said driver receiving configuration is used totransmit both linear and rotational forces in order to drive theabsorbable screw fastener. The absorbable screw fastener may bebioabsorbable. The body portion of the bioabsorbable fastener isthreaded, with the spacing between adjacent threads being augmented toprovide a wider pitch. In addition, the thread's outer diameter isenlarged creating substantially more land, giving the absorbable screwfastener greater stability and preventing dislodgement from the bodytissue. The absorbable screw fastener includes a cannulated center lumenwith an opening extending from the head portion through the longitudinallength of the body portion of the absorbable fastener. The head portionmay also include a flat segment, which may further extend to the outsideof the threads.

The subject of the invention achieves several very significantadvantages over the prior art. The low profile of the head portion(about 1.5 mm compared to about 5 mm of the body portion) reducesadhesion to the body tissue. The pitch configuration and the landcreated by enlarging the outer diameter of the thread enable thefastener to resist dislodgement. Finally, the driver receivingconfiguration on the head portion allows for torque and linear drivethus allowing for considerably less insertion force into the bodytissue.

Other features and advantages of the present invention will becomeapparent from the following detailed description, taken in conjunctionwith the accompanying drawings, which illustrate, by way of example, theprincipals of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present disclosure will be better appreciated byreference to the drawings wherein:

FIG. 1 is a perspective view of an absorbable screw fastener inaccordance with an embodiment of the present disclosure;

FIG. 2 is another perspective view of the absorbable screw fastener ofFIG. 1;

FIG. 3 is a longitudinal cross-sectional view of the absorbable screwfastener of FIG. 1 taken along line 3-3 of FIG. 1;

FIG. 4 is an orthogonal top view of the absorbable screw fastener ofFIG. 3;

FIG. 5 is a perspective view of an embodiment of a screw fastenerapplier according to an embodiment of the present disclosure;

FIG. 6 is a side view, with a housing half removed, of the housingportion of the screw fastener applier of FIG. 5 while in an initialposition;

FIG. 7 is a perspective view of a distal end of the screw fastenerapplier of FIG. 5;

FIG. 8 is a perspective partial cross-sectional view of the distal endof the screw fastener applier of FIGS. 5 and 6;

FIGS. 9-17 are partial cross-sectional side elevational views of thedistal end of the screw fastener applier of FIGS. 5-8, illustrating aseries of operational steps of the screw fastener applier for drivingthe absorbable screw fastener of FIGS. 1-4 into the target surgicalsite;

FIG. 18 is a perspective view of another embodiment of an absorbablescrew fastener of the present disclosure;

FIG. 18A is a longitudinal cross-sectional view of the absorbable screwfastener of FIG. 18 taken along line 18A-18A of FIG. 18;

FIG. 18B is a top view of the absorbable screw fastener of FIGS. 18 and18A;

FIG. 19 is a perspective view of a distal end of a screw fastenerapplier according to another embodiment of the present disclosure, withan end effector operatively secured thereto;

FIG. 20 is a perspective view of the distal end of the screw fastenerapplier of FIG. 19, with the end effector separated or disconnectedtherefrom;

FIG. 21 is a perspective view of the assembled cam spiral sub-assembly,inner tube sub-assembly and outer tube of the end effector according tothe present disclosure;

FIG. 22 is a perspective view of a cam spiral sub-assembly of the endeffector of FIG. 21 with the outer tube and inner tube sub-assemblyremoved therefrom;

FIG. 23 is a further perspective view of the cam spiral sub-assembly ofFIG. 22;

FIG. 24 is a perspective view of the cam spiral sub-assembly of FIGS. 22and 23, with a pusher and feed spring shown operatively associatedtherewith;

FIG. 25 is a perspective view of the cam spiral sub-assembly of FIG. 24,illustrating a screw fastener operatively associated therewith;

FIG. 26 is a perspective view of the cam spiral sub-assembly of FIGS. 24and 25, with a pair of screw fasteners operatively associated therewith;

FIG. 27 is a perspective view of the cam spiral sub-assembly of FIGS.24-26, with at least three screw fasteners operatively associatedtherewith;

FIG. 28 is a perspective view of the inner tube sub-assembly of the endeffector of FIGS. 21 and 28;

FIG. 29 is a perspective view of the cam spiral sub-assembly of FIG. 27operatively disposed within the inner tube sub-assembly of FIG. 28,while in a first position;

FIG. 30 is a perspective view of the cam spiral sub-assembly and innertube sub-assembly of FIG. 29, while in a second position;

FIG. 31 is a perspective view of the cam spiral sub-assembly of FIG. 27,while in the second position of FIG. 30;

FIGS. 32-36 illustrate a series of operational steps of the surgicalfastener applier including the end effector of FIGS. 19-31 for drivingthe absorbable screw fastener of FIGS. 18, 18A and 18B into the targetsurgical site;

FIG. 37 is a cross-sectional side perspective view of an absorbablescrew fastener according to a further embodiment of the presentdisclosure; and

FIG. 38 is a longitudinal cross-sectional view of the absorbable screwfastener of FIG. 37 taken along line 38-38 of FIG. 38.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Referring now in detail to the figures, which are included for purposesof illustration and not by way of limitation, an absorbable screwfastener of the present disclosure is illustrated in FIGS. 1-4, and isdesignated generally as absorbable screw fastener 10.

The presently disclosed embodiments of absorbable screw fastener 10contemplate the insertion of an absorbable screw fastener through atrocar into various tissue types using minimal application of force.Tissue typically wicks into the mesh in about 7-10 days, meaning thatthe fastener must maintain a certain structural integrity for at leastthat amount of time. Desirably, absorbable screw fastener 10 isconstructed so as to maintain its structural strength by about 80% forabout 10-21 days. Thereafter, the tissue will grow into the mesh and theabsorbable screw fastener 10 will be absorbed by the body at a fixedrate leaving in place only the mesh.

Although the specific focus of this disclosure will be on a laparoscopichernia repair, it will be noted that hernia repair is merelyrepresentative of a type of surgical procedure wherein absorbable screwfastener 10 can be utilized.

In the following description, as is traditional, the term “proximal”refers to the portion of the screw, applier or instrument closest to theoperator, while the term “distal” refers to the portion of the screw,applier or instrument remote from the operator.

Referring now to FIGS. 1-4, absorbable screw fastener 10 includes twomain components, namely a body portion 12 defining a longitudinal axis“X” and a substantially circular head portion 14 disposed on a proximalend of body portion 12. Absorbable screw fastener 10 further includes acentral cannulated opening or lumen 18 extending along the longitudinal“X” axis of body portion 12 and head portion 14 for receiving a matingpart therein, as will be described in greater detailed below. In oneembodiment, cannulated lumen 18 has a hexagonal traverse cross-sectionalprofile (not shown). Alternatively, it is envisioned that cannulatedlumen 18 may have a circular, rectangular or triangular traversecross-sectional profile.

Body portion 12 includes a helical thread 16 extending along a lengththereof, and may also include a truncated or blunt distal end 20.Further body portion 12 includes a center shaft 13 extending along alength thereof. Center shaft 13 and/or may have a constant outerdistance D1 and D2, or may taper from a larger proximal end to a smallerdistal end.

In one embodiment, head portion 14 has a distance “D” (of about 3.51 mm)which is approximately 54% of an overall length “L” (of about 6.5278 mm)of screw fastener 10. Additionally, body portion 12 has a length “L1”which is approximately 70-80% of the overall length “L” of screwfastener 10. In another embodiment, length “L1” is about 77% of theoverall length “L”. For example, head portion 14 may have a height orlength “L2” of about 1.5 mm and body portion 12 may have a length “L1”of about 5.0 mm. In yet another embodiment, distance “D” of head portion14 is substantially equal to an outer distance “D1” of body portion 12and helical thread 16.

The dimensions and physical characteristics of absorbable screw fastener10 are selected to insure a secure attachment of screw fastener 10 totissue. Similarly, the dimensions and physical characteristics ofapplicator 100 (FIG. 5) utilized to dispense screw fastener 10 intotissue are dependent upon the particular application.

With continued reference to FIGS. 1-4, head portion 14 includes driverreceiving recesses or structure, in the form of slots 28, formed in anouter radial surface of head portion 14. Slots 28 are configured totransmit torque to screw fastener 10. In one embodiment, a pair ofdiametrically opposed slots 28 are formed in head portion 14.Additionally, each slot 28 may be tapered at an angle toward thelongitudinal “X” axis extending distally from a proximal surface headportion 14. The taper of slots 28 helps to facilitates rotation anddriving of screw fastener 10. Alternatively or additionally, it isenvisioned that a torque transmitting feature may be provided on slots28, in the form of shoulders 26, or on the centrally cannulated opening18, in the form of a keyed surface (not shown). As described herein, thetorque transmitting feature allows for screw fastener 10 to be rotated.

With particular reference to FIG. 3, body portion 12 includes a singlecontinuous helical thread 16 thereon. Thread 16 includes an outerdistance “D1” which is substantially enlarged as compared to an innerdistance “D2” thereof. Having a substantially enlarged outer distance“D1” as compared to inner distance “D2” enables the tissue to more fullyand intimately adhere to the surface of screw fastener 10, consequentlyreducing instances of dislodgement of screw fastener 10. Thread 16 has apitch “P” (as seen in FIG. 1) between adjacent individual threads.

Thread 16 is also desirably tapered at both a distal lead-in 16 a and aproximal run-out 16 b. A space or gap 16 c is provided between proximalthread run-out 16 b and a distal surface of head portion 14. Gap 16 callows for the surgical mesh to rest therein. It is envisioned that thepitch of thread 16 may be larger or smaller depending on the particularsurgical procedure. Additionally, the cross-sectional shape of thread 16may be triangular, rectangular, etc.

As seen in FIGS. 1-4, screw fastener 10 may include at least one pair(three pairs shown) of diametrically opposed planer or flattenedsurfaces 22 formed in the outer radial surface of head portion 14 andhelical thread 16. Each planar surface 22 may additionally be in radialregistration with a respective slot 28. Planar surface 22 extendsdistally from head portion 14 to helical thread 16 of body portion 12and substantially along the entire length of body portion 12. Planarsurface 22 is provided for orientation of screw fastener 10 insidefastener applier 100, as will be described in detail below. It isenvisioned that other features may be provided for orientation of screwfastener 10 inside fastener applier 100.

Screw fasteners 10 may be fabricated from a medical bio-absorbablematerial such as for example, and not limited to, polyglycolic acid orpoly-Glycolide (PGA) and/or polylactic acid (PLA), L1 (18/82poly-Glycolide-co-L-lactide), L4 (42/58 poly-Glycolide-co-L-lactide),PGB (63/37 poly-Glycolide-co-Trimethylene Carbonate), any otherbiocompatible implantable material, or any combinations thereof. Screwfasteners 10 may be fabricated from a bio-absorbable material whichensures that screw fastener 10 maintains its structural integrity (e.g.,about 80% of original strength) for a predetermined period of time, suchas, for example, approximately 10 days. It is further contemplated thatscrew fastener 10, or a portion thereof, be coated with a biocompatiblematerial such as parylene, that may also be lubricious, and thatprovides for easier delivery of screw fastener 10 into tissue. But, moreimportantly, creating a longer absorption time of the surgical fastener10. Typically, such screw fasteners 10 are formed using an injectionmolding process as would be understood by one skilled in the art.

Desirably, absorbable screw fastener 10 may be delivered within anendoscopic 5 mm-diameter shaft of a fastener applier capable of firingmultiple fasteners. Components of an applier that may be used in thefiring of absorbable screw fasteners is shown and described in U.S. Pat.No. 5,830,221, the entire disclosure of which is incorporated herein byreference.

Referring now to FIGS. 5 and 6, a fastener applier for applyingabsorbable screw fasteners 10 is shown generally as fastener applier100. Fastener applier 100 generally includes a proximal housing portion112, which may be formed as two separate housing halves 112 a and 112 band a handle portion 114 extending from housing 112. A trigger 116 ismovably mounted to housing 112. Trigger 116 may be pivotally connectedto housing 112 with a free end of trigger 116 spaced from a free end ofhandle portion 114. This arrangement provides an ergonomic advantage andpositive secure control of trigger 116 and fastener applier 100.Fastener applier 100 also includes an elongated tubular portion 118extending distally from housing 112. The elongated tubular portion 118is provided to retain a plurality of screw fasteners 10 for applicationto body tissue. Elongated tubular portion 118 is dimensioned to fitthrough conventional endoscopic tubes or cannula structures insertedthrough small incisions in the body. In general, manipulation of controltrigger 116 results in ejection of screw fasteners 10, one by one, outof elongated tubular portion 118 and into body tissue.

With continued reference to FIG. 6, operation of housing portion 112 offastener applier 100 is described. In an initial or starting position,trigger 116 is biased away from handle 114 due to the force of returnspring 115. As shown, teeth 117 of gear portion 121 of trigger 116 areengaged with teeth 119 of trigger gear 123. As trigger 116 is squeezed,teeth 117 engage teeth 119 of trigger gear 123 to rotate driver gear151, which, in turn, rotates a first bevel gear 153 which, in turn,rotates a bevel drive gear 155 and ultimately cylindrical driver 144,fastener retainer 142 and pilot 140 (as seen in FIG. 8). Reference maybe made to U.S. Pat. No. 5,830,221, previously incorporated herein byreference, for a detailed discussion of the operation of housing portion112 of fastener applier 100.

Referring to FIGS. 7-8, elongated tubular portion 118 includes an outertube 136, defining a longitudinal axis “X1” and housing a cylindricaldriver 144. Cylindrical driver 144 generally includes a longitudinallyextending pilot 140, and a cylindrical fastener retainer 142 extendingalong the length of cylindrical driver 144. Fastener retainer 142 isconfigured to receive a plurality of screw fasteners 10 and pilot 140therein, such that upon rotation of cylindrical driver 144, screwfasteners 10 and pilot 140 are similarly rotated. A plurality of screwfasteners 10 may be arranged in a series longitudinally along the lengthof a distal portion of cylindrical driver 144. Each screw fastener 10 ispositionable within fastener retainer 142 of cylindrical driver 144.

Cylindrical driver 144 includes a pair of opposed resilient fingers ortabs 144 a extending from a distal-most end thereof. Each resilientfinger 144 a includes a distal tip 143 a angled and/or otherwiseoriented toward the longitudinal “X1” axis. As seen in FIG. 8, resilientfingers 144 a of cylindrical driver 144 hold or pinch a distal-mostscrew fastener 10 a in position ready for application. In particular,distal tip 143 a of each resilient finger 144 a of cylindrical driver144 is seatable in or receivable in respective slots 28 formed in headportion 14 of screw fastener 10 (see for instance FIG. 1). In operation,cylindrical driver 144 functions to engage a plurality of fasteners andto facilitate turning and driving/advancing of screw fasteners 10 intotissue.

Outer tube 136 may additionally be provided with a crenellated distaltip 136 a for engaging mesh overlying the surgical site in order tomaintain the mesh firmly in position and prevent the mesh from thrustingor otherwise spinning or bunching while absorbable screw fastener 10 istorqued and driven through the mesh. Crenellated distal tip 136 a, ofouter tube 136, may be of various geometric shapes and dimensions,(e.g., serrated, saw-toothed, etc.), or may be omitted completely.

Pilot 140 functions as a guide to aid in the insertion of screw fastener10 into tissue. Pilot 140 includes a sharpened distal tip 140 a fortapping the mesh and underlying target tissue prior to insertion ofscrew fastener 10. Distal tip 140 a of pilot 140 is shown with an angledtip. In an alternative embodiment, distal tip 140 a of pilot 140 may beof various geometries. Referring to FIGS. 9-10, retaining feature 148,provided on pilot 140, holds a distal-most screw fastener 10 a in placeas will be described below. In a loaded position, fastener applier 100includes at least one screw fastener 10 disposed in or retained infastener retainer 142 such that pilot 140 extends through cannulatedopening 18 of screw fastener 10. As explained above, slots 28 of headportion 14 of screw fastener 10 are engaged by respective tips 143 a offingers 144 a of cylindrical driver 144. Tips 143 a of fingers 144 a ofcylindrical driver 144 are configured and dimensioned to engage and/orbe received in respective slots 28 formed in head portion 14 of screwfastener 10.

A method of inserting absorbable screw fastener 10, using fastenerapplier 100, will now be discussed. Referring to FIGS. 5, 6 and 9-17,distal tip 136 a of outer tube 136 is initially placed against the meshand/or the target tissue. Advantageously, crenellated tip 136 a of outertube 136 securely engages the mesh and helps to prevent movement of themesh relative to the tissue. The user then pushes distal tip 136 a ofouter tube 136 against the target mesh or tissue. In so doing, a spring(not shown) is compressed allowing outer tube 136 to retract proximally,in the direction of arrow “A” (see FIG. 9), and thus unlocking a triggerlock (not shown).

As a safety feature, as seen in FIG. 10, pilot 140 remains within outertube 136 even when outer tube 136 is fully retracted. This safetyfeature prevents accidental contact or pricking with distal tip 140 a ofpilot 140.

Referring now to FIGS. 6, 11 and 17, with outer tube 136 in the fullyretracted position, fastener applier 100 is capable of firing screwfastener 10 therefrom. To drive and/or expel fastener(s) 10 fromfastener applier 100, trigger 116 is drawn toward handle 114 against thebias of return spring 115. As trigger 116 is moved, teeth 117 on gearportions 121 of trigger 116 engage and rotate teeth 119 of trigger gear123 clockwise, ultimately causing cylindrical driver 144, fastenerretainer 142 and pilot 140 to be driven (axially in the direction ofarrow “B”) and rotated (about the longitudinal “X1” axis) until pilot140 extends beyond distal tip 136 a of outer tube 136 of fastenerapplier 100, as shown in FIG. 11. In one embodiment, pilot 140 extendsbeyond distal tip 136 a of outer tube 136 by an amount approximatelyequal to 3 mm. Feed spring 145 acts on a plunger 147 to bias plunger 147against the proximal-most screw fastener and maintain a force in thedistal direction on the column of screw fasteners 10 disposed withinfastener retainer 142.

As shown in FIG. 12 and as will be discussed in greater detail below,once pilot 140 has stopped moving distally, cylindrical driver 144 andfastener retainer 142 continue to be driven and rotated distally untilhead portion 14 of a distal-most absorbable screw fastener 10 a issubstantially in line with distal tip 136 a of outer tube 136 thuspreventing insertion of distal-most screw fastener 10 a beyond distaltip 136 a of outer tube 136. As shown in FIG. 12, cylindrical driver 144drives and rotates distal-most screw fastener 10 a completely over andbeyond retaining feature 148 of pilot 140. Additionally, retainingfeature 148 acts as a stop to the distal advancement of an adjacentabsorbable screw fastener 10 b, adjacent distal-most screw fastener 10a, until adjacent screw fastener 10 b is engaged and advanced bycylindrical driver 144.

Retaining feature 148 may be in the form of a C-ring, compressibleO-ring, a crimp or bump in the cannulated lumen 18 (see FIG. 15A) or thelike, wherein retaining feature 148 has an initial dimension which isgreater than the dimension of cannulated lumen 18 of screw fastener 10.Accordingly, when distal-most screw fastener 10 a initially engages orcontacts retaining feature 148, since retaining feature 148 is sized tobe larger than cannulated lumen 18, distal-most screw fastener 10 a isprevented from passing. However, as the force being applied todistal-most screw fastener 10 a is increased, retaining feature 148 iscaused to be squeezed into cannulated lumen 18 as distal-most fastener10 a is advanced. Distal-most fastener 10 a is forced entirely acrossretaining feature 148 such that the retaining feature passes throughcannulated lumen 18 and exits a proximal end thereof. The column ofscrew fasteners, behind distal-most fastener 10 a is then distallyadvanced by the force of feed spring 145. However, the force of feedspring 145 is not great enough to cause retaining feature 148 to besqueezed into the next screw fastener. Accordingly, retaining feature148 prevents the distal advancement of the column of screw fasteners.

Once trigger 116 has been completely depressed and distal-most screwfastener 10 a is driven through the mesh and into the tissue, the userreleases trigger 116 and a two stage release cycle begins. Referring toFIG. 13, while fastener retainer 142 remains fixed in place, cylindricaldriver 144 is retracted in a proximal direction (e.g., in the directionof arrow “C”). Cylindrical driver 144 is not rotated and drawn in aproximal direction so that distal-most fastener 10 a is not unscrewed.As cylindrical driver 144 is retracted resilient fingers 144 a deflector cam radially outward as resilient fingers 144 a slide over thetapered surface of slots 28 a to disengage slots 28 a of head portion 14a of distal-most screw fastener 10 a and release distal-most screwfastener 10 a. In addition, as cylindrical driver 144 is retractedresilient fingers 144 a are cammed radially outward by theirinter-engagement with fastener retainer 142. Cylindrical driver 144 maybe retracted until a distal-most tip of resilient fingers 144 a issubstantially aligned with a distal-most edge of fastener retainer 142.

Referring now to FIG. 14, pilot 140 is proximally retracted until pilot140 is disposed within outer tube 136 such that distal tip 140 a ofpilot 140 is not longer exposed. Additionally, cylindrical driver 144and fastener retainer 142 are proximally retracted until tips 143 a ofresilient fingers 144 a of cylindrical driver 144 are aligned with slots28 b formed in head portion 14 b of adjacent screw fastener 10 b. In analternative embodiment, cylindrical driver 144 and pilot 140 may retractindependently of one another or simultaneously.

Referring now to FIG. 15, while screw fastener 10 b is maintained inposition by retaining feature 148, fastener retainer 142 is proximallyretracted, to its starting position, as shown in FIG. 8, so that tips143 a of resilient fingers 144 a of cylindrical driver 144 return totheir un-deflected position and engage slots 28 b of head portion 14 bof adjacent screw fastener 10 b. Since fastener retainer 142 has alonger stroke to return to its starting position as compared tocylindrical driver 144 resilient fingers 144 a of cylindrical driver 144flex back down and engage adjacent screw fastener 10 b. Referring toFIG. 16, outer tube 136 is returned to its starting position, as shownin FIGS. 9 and 17. In alternative embodiments, distal movement of outertube 136 to its starting position can be accompanied by an audibleand/or tactile response heard/felt by the end user. In alternativeembodiments cylindrical driver 144 and fastener retainer 142 canproximally retract together.

In an embodiment, housing 112 may be fabricated to have a reusablehandle portion 114 and trigger 116 that can be re-sterilized, and adisposable elongated tubular portion 118. Thus, upon discharge of allthe screw fasteners 10 elongated tubular portion 118 would be discardedand replaced, housing portion 112 would be sterilized and reused up to alimited number of procedures.

In other embodiments, revolving means to cause cylindrical driver 144 torotate may include a single knob connected to a rotator which can beturned by hand. Additionally, the revolving means may include a rack andgear structure or a set of beveled gears.

FIGS. 18, 18A and 18B present another possible embodiment of theabsorbable screw fastener. Screw fastener 200 is similar to screwfastener 10 and will only be discussed in detail to the extent necessaryto identify differences in construction and/or operation. In oneembodiment, body portion 212 of screw fastener 200 has a uniformdistance along at least a portion of, desirably along its entire, lengthwhich is equal to inner distance “D2”. Also, distance “D1” of bodyportion 212 may be tapered from a narrow, blunt distal end 220 to alarger proximal end where it transitions into the outside diameter ofproximal head portion 214 to increase torque strength. The gradual taperalong body portion 212 allows a small footprint of screw fastener 200when entering the mesh, and growing radially outward along the length ofbody portion 212 for better rates of absorption into the body and thentransitions into the outside diameter of head portion 214 to help resisttorque. In addition, slots 228, formed in head portion 214 are parallelto the longitudinal axis “X” axis and extend the entire thickness ofhead portion 214.

With reference to FIGS. 19-21, an end effector for engagement with adistal end of elongated tubular portion 118 of fastener applier 100, tobe used for the application of screw fasteners 10 or 200 or forretaining screw fasteners 10 or 200, is generally designated as 202. Endeffector 202 may take the form of a disposable loading unit (DLU) orsingle use loading unit (SULU) which retains a load of fasteners 10 or200 therein, and which may be disposed of or replaced or may besterilized, re-loaded and reused.

Referring initially to FIGS. 19-21, end effector 202 includes an outertube 236, defining longitudinal axis “X2” and housing an inner tubeassembly 238 for retaining screw fasteners 200 therein, a cam spiraldriver 244 supported on the distal end of tubular portion 118, a pin 254and a cam spiral sub-assembly 248 disposed in inner tube assembly 238and operatively connected to cam spiral drive 244.

End effector 202 is attached to or formed integral with the distal endof elongated tubular portion 118 of fastener applier 100 such that whencontrol trigger 116 of fastener applier 100 is drawn toward handle 114,cam spiral driver 244 rotates (similar to the rotation of cylindricaldriver 144 described above). Cam spiral sub-assembly 248 includes ahelical thread 248 a, which mates with and receives a pin 246 of camspiral driver 244 so that when cam spiral driver 244 rotates, cam spiralsub-assembly 248 rotates and translates, as discussed in detailhereinbelow.

Referring to FIGS. 22 and 23, cam spiral sub-assembly 248 will bediscussed in detail. Cam spiral sub-assembly 248 includes a cam spiral250 having a proximal end 250 a defining a helical thread 248 a, pilot240 extending longitudinally from a distal end 250 b of cam spiral 250,and a fastener retainer 242 operatively supported on distal end 250 b ofcam spiral 250. Cam spiral sub-assembly 248 is assembled in such amanner that upon rotation of cam spiral 250, pilot 240 and fastenerretainer 242 are similarly rotated. In alternative embodiments, camspiral sub-assembly 248 may be fabricated as a single part/component.Fastener retainer 242 may include a pair of opposed longitudinallyextending rails 242 a which act as retainers or guides for screwfasteners 200. A distal end 243 a of rails 242 a will also act as adriver for screw fasteners 200, as will be described hereinbelow.Desirably, a distal end 240 a of pilot 240 extends distally of distalend 243 a of rails 242 a and fastener retainer 242. A pin 254 (see forinstance FIG. 21) is received in and extends radially from a slot 250 cformed in cam spiral 250.

A seen in FIGS. 24-27, cam spiral sub-assembly 248 further includes afeed spring 245 and a screw fastener pusher 247, each disposed on pilot240 and within fastener retainer 242. As shown in FIGS. 25-27, rails 242a of fastener retainer 242 orients screw fasteners 200 by engagingrespective slots 228 in head portion 214 of screw fastener 200.Desirably, feed spring 245 is disposed between screw fastener pusher 247and cam spiral 250. As such, feed spring 245 biases pusher 247 in adistal direction.

Multiple screw fasteners 200 may be retained in or operativelyassociated with cam spiral sub-assembly 248, for example, one (1) asseen in FIG. 25, two (2) as seen in FIG. 26, or three (3) as seen inFIG. 27. While one to three screw fasteners 200 are shown in FIGS.25-27, it is understood that the present device may be used with or mayaccommodate any number of screw fasteners 200.

Referring now to FIG. 28, in an alternate embodiment or additionally,inner tube sub-assembly 238 includes a cylindrical body 260, a torquering 262 operatively connected to a distal end 260 a thereof, and aretaining ring 264 operatively connected to torque ring 262. Cylindricalbody 260, includes a transversely oriented rotational slot 260 b formedtherein for slideably receiving pin 254 extending from cam spiral 250.Rotational slot 260 b limits the movement of pin 254 and, in turn, therotation of cam spiral driver 244. Rotational slot 260 b may be sized tolimit the rotation to about 90 degrees. With continued reference to FIG.28, torque ring 262 includes a pair of diametrically opposed engagementfeatures 262 a extending radially inward therefrom. Engagement features262 a are desirably sized to mate with corresponding slots 228 of headportion 214 of screw fastener 200. Retaining ring 264 includes two pairof diametrically opposed tabs 264 a, 264 b extending radially inwardtherefrom. Tabs 264 a, 264 b may be offset by about 90 degrees relativeto one another. Desirably, one pair of tabs 264 a is axially alignedwith engagement features 262 a of torque ring 262. Tabs 264 a, 264 bhold distal screw fastener 200 in place and prevent feed spring 245 ofcam spiral sub-assembly 248 from driving all the internal screwfasteners 200 out from the instrument in one rapid fire sequence.

Inner tube sub-assembly 238 may be constructed from several differentcomponents mounted or otherwise operatively connected to one another toform a unitary inner tube sub-assembly 238 or may be manufactured as asingle component.

Referring now to FIGS. 29 and 30, inner tube sub-assembly 238 is shownoperatively associated with (e.g., rotatably supported on) cam spiralsub-assembly 248. As described above, pin 254 extends through rotationalslot 260 b of inner tube sub-assembly 238. Accordingly, inner tubesub-assembly 238 and cam spiral sub-assembly 248 act as one unit whencam spiral sub-assembly 248 is activated, as will be described ingreater detail below.

In FIG. 29, inner tube subassembly 238 is shown in a first position withrespect to cam spiral sub-assembly 248 and with pin 254 located at oneend of rotational slot 260. In FIG. 30, inner tube sub-assembly is shownin a second position with respect to cam spiral sub-assembly 248 andwith pin 254 located at an opposite end of rotational slot 260.

Turning now to FIGS. 31-36, a method of inserting absorbable screwfastener 200 or 10 will be discussed. Referring to FIGS. 32 and 33, adistal tip 236 a (shown crenellated) of outer tube 236 is initiallyplaced against the mesh and/or the target tissue. In so doing, distaltip 236 a of outer tube 236 helps to maintain outer tube 236 flyconnected to the mesh and keeps the mesh taught.

Next, the trigger of the fastener applier is actuated (e.g., squeezed)to rotate cam spiral driver 244 and to rotate and translate cam spiralsub-assembly 248 and inner tube sub-assembly 238. Holding outer tube 236in a stationary position, a distal-most screw fastener 200 a is advanceddistally as shown in FIGS. 34 and 35. In particular, as cam spiralsub-assembly 248 is rotating and translating to drive distal-most screwfastener 200 a forward, inner tube sub-assembly 238 rotates distal-mostscrew fastener 200 a.

As seen in FIG. 36, cam spiral sub-assembly 248 (see FIG. 34) will drivedistal screw fastener 200 a an amount sufficient to push distal-mostscrew fastener 200 a beyond tabs 264 b of retaining ring 264 (see FIG.28) and thus releasing distal-most screw fastener 200 a from theremainder of the fastener applier.

Desirably, when the trigger of the fastener applier is released, allinternal sub-assemblies retract and reorient themselves, thus allowingfeed spring 245 to advance the next screw fastener into torque ring 254.

Turning now to FIGS. 37 and 38, another possible embodiment of theabsorbable screw fastener, is shown generally as 300. Screw fastener 300is similar to screw fastener 10 and will only be discussed in detail tothe extent necessary to identify differences in construction and/oroperation.

Screw fastener 300 includes a body portion 312 defining a longitudinalaxis “X” and a substantially circular head portion 314 disposed on aproximal end of body portion 312. Body portion 312 includes a helicalthread 316 extending along a length thereof, and terminates in a distalend 320. In the present embodiment, helical thread 316 is tapered totangency at the distal end for ease of insertion purposes. The proximalend of helical thread 316 stops before a distal surface of head portion314 to create gap 316 c in which the mesh (not shown) may be received.

Distal end 320 of body portion 312 defines a distal surface 320 a whichis angled with respect to the “X” axis by an angle Θ. In one embodiment,angle Θ of distal surface 320 a is from about 5° to about 15° withrespect to an axis “Y” which is orthogonal to the “X” axis. In yetanother embodiment, angle Θ is about 9°. Further, body portion 312includes a center shaft 313 extending along a length thereof. In oneembodiment, center shaft 313 is tapered to have a smaller distal end anda larger proximal end in order to increase the ease of insertion ofscrew fastener 300.

With continued reference to FIGS. 37 and 38, head portion 314 includesdriver receiving recesses or structure, in the form of slots 328, formedin an outer radial surface of head portion 314. Slots 328 are configuredto transmit torque to screw fastener 300. In one embodiment, a pair ofdiametrically opposed slots 328 are formed in head portion 314. Eachslot 328 may be parallel to the longitudinal “X” axis, and extendthrough a distal surface 314 a and a proximal surface 314 b of headportion 314. Slots 328 extend the entire length of screw fastener 300 todefine corresponding slots 328 a-328 d formed in helical thread 316.

In one embodiment, head portion 314 has a low profile, i.e., headportion 314 has a length “L2” which is about 1.5 mm and a distance ofabout 3.81 mm. Also, body portion 312 may have a length “L1” which isabout 5.0 mm. As such, the overall length “L” of screw 300 is about 6.5mm.

Alternatively or additionally, it is envisioned that a torquetransmitting feature may be provided on slots 328, in the form ofshoulders 326, the torque transmitting feature allowing for screwfastener 300 to be rotated.

Distal surface 314 a may also be angled as shown with respect to the “X”axis by an angle Φ. In one embodiment, angle Φ of distal surface 314 ais from about 5° to about 15° with respect to an axis “Y” which isorthogonal to the “X” axis. In yet another embodiment, angle Φ is about9°. The angle of distal surface 314 a is provided to help with theremoval of screw fastener 300 in the event that screw fastener 300 needsto be removed from the surgical site.

A space or gap 316 c may be provided between a proximal thread run-outand distal surface 314 a of head portion 314. Gap 316 c allows for thesurgical mesh to rest therein. It is envisioned that the pitch of thread316 may be larger or smaller depending on the particular surgicalprocedure.

As seen in FIG. 37, each slot 328 a-328 d includes a radiused distal orleading edge 329 a and a radiused proximal or trailing edge 329 b.Radiused leading edge 329 a and radiused trailing edge 329 b help tofacilitate insertion of and removal of screw fastener 300 into and fromthe surgical site.

From the foregoing, it will be appreciated that the screw fastener andfastener applier of the present invention cooperate to securely attach afastener with high retentive surface area, to tissue, from onedirection, through the utilization of a fastener applier having asimpler design. It is also to be appreciated that the present inventionmay be utilized in a number of applications including ligating tissue,hernia mesh repair, bladder neck suspension, arthroscopic knee surgery,and in conjunction with implant drug delivery systems or proceduresinvolving positioning of surgical or implantable devices in patients.

While several particular forms of the invention have been illustratedand described, it will also be apparent that various modifications canbe made without departing form the spirit and scope of the invention.

Thus, it should be understood that various changes in form, detail andapplication of the present invention may be made without departing formthe spirit and scope of the invention.

1. An instrument for inserting an absorbable screw fastener, theinstrument comprising: a distal portion having an elongated outer tube;a proximal portion having a trigger mechanism; and a driver/torquesubassembly disposed within the outer tube and being movable relative tothe outer tube including at least a pair of resilient force transmittingarms extending distally therefrom, wherein the arms provide at least apartial passage for a fastener therethrough, to selectively retain ahead of an absorbable screw therebetween, and to transmit both an axialand a rotational force to the absorbable screw.
 2. The instrument ofclaim 1, wherein the outer tube defines a crenellated tip.
 3. Theinstrument of claim 1, wherein the trigger mechanism comprises a ratchetmechanism.
 4. The instrument of claim 1, wherein the outer tube isbiased to a distally advanced position.
 5. The instrument of claim 1,further comprising a pilot disposed within the outer tube, the pilothaving a tapered surface on its distal end.
 6. The instrument of claim1, further comprising a fastener retainer dimensioned to receivefasteners.
 7. An absorbable screw fastener and instrument for insertingthe absorbable screw fastener, comprising: an instrument having an outertube on a distal end and a trigger mechanism on its proximal end; adriver/torque subassembly disposed within the outer tube, thedriver/torque subassembly including at least a pair of resilient forcetransmitting arms extending distally therefrom; and an absorbable screwfastener having a body portion and a head portion disposed at theproximal end of the body portion, the fastener being inserted on thedistal end of the instrument, the head of the absorbable screw fastenerhaving a driver receiving configuration formed in an outer radial sidesurface of the outer diameter for selective engagement with at least thepair of resilient force transmitting arms of the drive/torquesubassembly, wherein the resilient force transmitting arms allow atleast a partial passage for the fastener therethrough, wherein theresilient force transmitting arms transmit both linear and rotationalmotion to the driver receiving configuration of the absorbable screwfastener.
 8. The absorbable screw fastener and instrument of claim 7,wherein the driver receiving configuration further defines a slot formedin the surface of the outer diameter of the head portion, wherein theslot of the screw fastener extends the entire length thereof.
 9. Theabsorbable screw fastener and instrument of claim 8, wherein theabsorbable screw fastener is formed of a material selected from thegroup consisting of L1, L4, PGA, and PGB.
 10. The absorbable screwfastener and instrument of claim 7, wherein the distal end of the bodyportion defines a distal surface which is angled with respect to thelongitudinal axis.
 11. The absorbable screw fastener and instrument ofclaim 10, wherein the distal surface of the distal end of the bodyportion is angled at about 5° to about 15° with respect to an axis whichis perpendicular to the longitudinal axis.
 12. The absorbable screwfastener and instrument of claim 7, wherein the head portion defines adistal surface which is angled with respect to the longitudinal axis.13. The absorbable screw fastener and instrument of claim 12, whereinthe distal surface of the head portion is angled at about 5° to about15° with respect to an axis which is perpendicular to the longitudinalaxis.
 14. The absorbable screw fastener and instrument and instrument ofclaim 13, wherein the distal surface of the distal end of the bodyportion is angled at about 5° to about 15° with respect to an axis whichis perpendicular to the longitudinal axis.
 15. The absorbable screwfastener and instrument of claim 14, wherein each slot formed in eachthread includes at least one of a radiused leading edge and a radiusedtrailing edge.